Honey Brew
by Umeko Tsumagoi
Summary: Hogwarts AU. Hajime and Fuyuhiko want to swap places. Fortunately, they're at Hogwarts so that's actually totally possible.


**Notes:** I wasn't going to write any more Hogwarts AU until after I got the next chapter of "Waiting for Rainbows" posted. In fact, I wasn't even going to write this fic at all, because I only had some disjointed scenes in mind, not a cohesive story with seamless transitions and all.

But then I realized **IT'S KUZUHINA WEEK 2018** and I wanted to post something in addition to the Rainbows chapter which will take another few days, so why _shouldn't_ I just write those disjointed scenes as-is?! I might change the title later though, I couldn't think of anything hfhdshjshk

So here we are. This is the same AU as my previous fic, "Where Time Has No Name," but it's not absolutely necessary to read that first. I'd kind of recommend that you do just for background, but hey, you do you.

This is unbetaed af, but I hope you enjoy!

* * *

 **Honey Brew**

 **1**

"Hey, what if we swapped Houses for a day?"

Hajime couldn't see Fuyuhiko's facial expression, as they were sitting with their backs against each other, but he assumed he was joking and answered with a laugh. "Yeah, I wish."

"No, really. What if we disguised ourselves as each other and swapped Houses for a day?"

Hajime frowned down at his Herbology homework; so the other boy was being serious? "Uh, I'm not sure we can convincingly... pull off those disguises," he said, careful not to touch on specifics. Hajime had hit a major growth spurt a few months earlier, right around his fifteenth birthday, and Fuyuhiko hated being reminded that the Slytherin was now more than half a head taller than him.

He felt Fuyuhiko shift behind him, and he braced himself against the back of the couch before he could fall over backwards. "Look, I dunno if you forgot what school we're at, but here—" Fuyuhiko shoved his open Potions textbook in front of Hajime's face "—Polyjuice Potion. You've heard of it?"

"Isn't that supposed to be crazy advanced?" Hajime skimmed the page in front of him to confirm that yes—it _was_. "I don't think either of us can brew this, Fuyuhiko."

"So we'll get someone to help," Fuyuhiko said easily as he took the book back. "Isn't Slughorn your Head of House? Ask him for a favor."

"I doubt that Slughorn will— wait, first of all, _why_?!" Hajime turned around to face Fuyuhiko. "Don't you think this idea is just a little bit ridiculous?"

"You're the one who just said you wish we could switch," Fuyuhiko pointed out, a smug grin on his face.

"That was hyperbole."

"Was it, though?"

Hajime was silent, pulling his mouth into a thin line. He couldn't deny that giving Hufflepuff a try was a tempting idea; while he had gradually grown to appreciate most of his Slytherin housemates, it _would_ be fun to try spending his school life with his best friend and his cousin.

"That's what I thought." Fuyuhiko crossed his arms, smirking triumphantly. "So you're in?"

"I didn't say that." Hajime paused, then sighed. "But sure, if we can find a way to make this work, why not?"

"That's the spirit." Fuyuhiko cleared the scattered parchment off the couch to place the Potions book between them. "Anyway, even if Slughorn's out of the question, I figure that between the two of us we should know if there's _someone_ in our year who can do this. I mean, I've heard the Ravenclaws in my class talk about some fifth-year Potions genius in their House, but it would be shitty to pester someone who's preparing for her O.W.L.s..."

"Uhh..." Hajime racked his brain, mentally ticking off all the students in his own Potions class. "Yeah, I don't know if there's anyone in Slytherin or Gryffindor who's particularly— wait..."

Fuyuhiko arched an eyebrow. "Yeah?"

After hesitating for just a moment, Hajime continued. "There's one guy in Gryffindor who— well, I've never noticed if he's particularly talented at Potions, but he tends to always look... different."

"Different?"

"Like..." Hajime gestured vaguely with his hands. "He always comes to class with different hair, or different eyes, or a different face entirely. Everyone calls him the Imposter. So..."

Fuyuhiko's golden eyes gleamed. "You think he uses Polyjuice Potion?"

"I mean, I don't know why he _would_ , but it's possible? That or he's a Metamorphmagus."

"Come on, what are the chances that there are _two_ Metamorphmagi in our year?" Fuyuhiko rolled his eyes. "Anyway, we'll make him our plan A for now. Ask him what his deal is next time you see him."

 **2**

"Both."

Hajime blinked blankly at the Imposter. "Sorry, what? What do you mean, 'both'?"

"It's the answer to your question. I do have some degree of metamorphic ability," the Imposter said, sounding bored with the explanation as he packed up at the end of class. "But I've also been experimenting with Polyjuice Potion to help hone my skill. It opens the door to possibilities that I wouldn't have otherwise."

"What other possibilities could you want?" Hajime gaped openly as he followed the other boy out of the Potions dungeon. "I mean, if you're already a Metamorphmagus, isn't that amazing enough?"

The Imposter sighed. "There are limits to what I can change with my innate ability. Height, weight, sex, vocal cords..."

"You can't even change your own vocal chords?"

The Imposter stopped just before turning a corner, gazing sharply at Hajime—his eyes were almond-shaped and ice blue today, he couldn't help but notice. "Hinata. I can't imagine that you'd approach me out of the blue to chat about this. If you want help with a Polyjuice Potion, just ask."

"Ah..." Hajime grinned sheepishly. "It's that easy?"

"As long as you don't have evil intentions—and I don't sense that you do—I don't mind helping my classmates out in their endeavors." The Imposter shrugged.

"Don't you want to know what I want to use it for though?"

"It's no more my business than mine is yours."

Hajime winced. "Fair enough... sorry for the probing questions, then."

The Imposter shrugged again. "In any case, my current brew lasts about four hours, but I'll have one done in a few weeks that may last a bit longer. Beyond that... we're getting close to the end of term, so I wasn't planning on starting another brew before the summer, but..."

"Ah, no, that's fine!" Hajime waved his hands dismissively. "The current brew is fine! Just, uh... if it's not a problem, I need enough for two people, please."

 **3**

"Well, fuck me." Fuyuhiko gazed at the two vials in his hand in wonder, careful not to drop them in his soup. "I can't believe it was actually that easy."

"Right?" Across the table, Hajime laughed. "He even gave me four doses, so we can each get eight hours out of it. Those are both yours, by the way."

Fuyuhiko tucked the vials into his robes and returned to his dinner. "Eight hours... that's pretty good. Enough for a full day of classes. When do you want to use it, then?"

Hajime tilted his head to the side in thought as he picked at a dinner roll. "I mean, what about tomorrow? The potion's ready to use as soon as we add our hair, so there's no reason to wait..."

"Nah." Fuyuhiko shook his head and took a sip of soup before continuing. "I've got a test in Charms tomorrow, so it needs to be another day."

Hajime was silent for a moment, his brows furrowed in thought. "You know... Charms is my best subject, so if you wanted—"

He didn't get to finish his thought, breaking off into a pained wince as Fuyuhiko's foot sharply met his shin.

"We're doing our _own_ schoolwork, dumbass."

 **4**

A week later, an hour before classes started for the day, Hajime headed for the seventh floor of the castle. He wasn't entirely convinced that the Room of Requirement would be available—maybe someone was using it for some last minute homework cramming before class—but sure enough, after pacing the area three times, the door appeared to let him into his and Fuyuhiko's regular room.

"About time you got here, dumbass," Fuyuhiko said as he stood up from the couch. "I'm not gonna have time for breakfast at this rate."

"Sorry. How'd you know we'd be able to use this room, though?"

Fuyuhiko shrugged. "I grabbed it as soon as it freed up after dinner yesterday and spent the night."

"You did? I would have spent the night too if I knew..."

The Hufflepuff made a face. "Why the hell would you?"

"Uh..." Hajime faltered; he hadn't really thought about what he was saying. "I mean, it would have been like... a sleepover? We just don't get the chance to do that often, I guess..."

Fuyuhiko rolled his eyes, his cheeks tinged pink. "Idiot. If that's what you want you can just visit our vacation home this summer."

"What? You mean the one in Sicily?"

Fuyuhiko answered by shoving his yellow-lined robes into Hajime's arms. "We'll talk about that later. Right now let's take the potion and get to class."

"Oh... right." Hajime quickly shedded his own Slytherin robes and was about to walk towards a different corner of the room to take his potion when he paused and turned back towards Fuyuhiko. "Hey, you uh... before you drink the potion, you should probably take the rest of your clothes off too."

Within seconds, Fuyuhiko's face grew to an impressive shade of red. "Wh— why the hell should I, bastard?!"

"Well, because, I mean..." Hajime stumbled over his words, feeling his own face growing hot. "When you turn into me, your clothes won't fit, so it's probably a good idea to undress first..."

Shaking off his embarrassment, Fuyuhiko shifted into a dark glower. "And why won't my clothes fit?"

Hajime blinked owlishly. "Um..."

"Go on. Tell me why my clothes won't fit. I dare you."

Deciding that it was best to retreat, Hajime silently turned around and walked to the far corner, hoping that their size difference wasn't enough to result in stretched fabric and ripped seams.

 **5**

Underneath his clothes, Fuyuhiko was even smaller than he seemed. It wasn't like Hajime was exactly _swimming_ in his own clothing after transforming into his friend, but there was definitely enough bagginess to require the spare uniform Fuyuhiko had supplied.

As he began unbuttoning his shirt, Hajime watched Fuyuhiko's chest gradually coming into view. Yeah, it wasn't just his height; his torso wasn't nearly as broad as Hajime's. It was strange being in a body so drastically different from his own.

With the shirt fully unbuttoned, Hajime experimentally ran his hands across Fuyuhiko's flat stomach towards his hips. Gosh, he was _skinny_. Now that Hajime thought of it, the Hufflepuff didn't seem to have grown much since they first met a year and half earlier. Maybe he was just a late bloomer and hadn't had a growth spurt yet?

Hajime was suddenly stuck by the absurdity of the situation and removed his hands, trying to ignore the way his stomach felt like it was knotting up. He didn't think the potion would have made him nauseated—it had actually tasted pretty good, almost like honey—but maybe he was still reeling from the actual transformation.

He finally shedded the shirt completely and blinked at Fuyuhiko's arms, realizing that he couldn't remember ever seeing the boy in short sleeves. "Hey," he said aloud, jumping a bit in surprise at hearing Fuyuhiko's voice come from his mouth. "I didn't know you also had freckles all up your arms and... oh, on your shoulders, too..."

"Don't _look_ at me!" Hajime's own voice shouted from the other side of the room, before being followed up by the sound of foodsteps and a sharp pain in Hajime's right calf. "And you better not do anything weird with my body, jackass!"

"Says the one who just kicked himself..."

 **6**

Hajime's legs were _long_.

Not that they were noticeably longer than Fuyuhiko's or anything like that—of course they weren't, it wasn't like Hajime was a lot taller or anything—but damn, how did he even walk in those things. For the first few minutes in Hajime's body, Fuyuhiko felt like he was walking on stilts.

Really short stilts. Like, stilts that were _maybe_ an inch tall. No more than that, no way.

Fuyuhiko took his time walking down the flights of stairs, almost overstepping and landing on a trick step more than once, but he and Hajime managed to make it to the third floor just as the rest of the student body was filing into the hallway from breakfast.

After parting ways with Hajime, who headed to Defense Against the Dark Arts with the Hufflepuffs, Fuyuhiko scoured the crowd and managed to locate his sister and Peko walking towards the Charms corridor.

"Hey!" he called out to them, causing both girls to stop and turn towards him. He made his way through the crowd as quickly as possible.

As soon as Fuyuhiko reached them, Natsumi peered up at him suspiciously. "What the hell are you doing here?" she snapped.

Fuyuhiko fought the urge to scowl at his sister; he realized, belatedly, that he would have to act like Hajime. He wasn't an actor by any stretch of the imagination, but he still tried to put on his interpretation of a Hajime-esque goofy smile. "What do you mean?" he asked.

Natsumi didn't answer, instead doubling over in laughter, so Peko took over. "Fuyuhiko, why are you in Hajime's body?"

"Wh—" Fuyuhiko gaped; had he really been found out _instantly_? "I don't know what you're talking abo—"

"Your gait," Peko said simply.

"Yeah," Natsumi agreed, managing to quiet her sniggers to an acceptable volume. "I mean you're walking like a stiff wind could blow you over at any moment, but besides that you're moving like my dope of a brother, not Hajime. It's actually kinda gross." She shivered. "Too creepy, I can't bear to see this anymore. I'm off to Charms, bye!" With that, Natsumi left down the corridor, her long hair whipping behind her.

Once she was gone, Peko looked up at Fuyuhiko again, a silver eyebrow arched inquisitively. "Explain?"

Fuyuhiko gave a defeated sigh. "Me and Hajime are switching places for the day, okay? Don't make a big deal out of it."

Peko sighed. "If you say so. I won't tell anyone, but I'll be interested to see how well you can pull off Hajime."

"How hard can it be to pretend to be a way-too-nice dumbass?"

With a shake of her head, the silver-haired girl allowed herself a fond smile.

 **7**

Hajime was a bit surprised that he didn't have much trouble following Fuyuhiko's classes—the Hufflepuffs were slightly ahead of Slytherin in the Defense Against the Dark Arts curriculum, and Hajime hadn't even signed up for Care of Magical Creatures, but he got through those classes without arousing any suspicion. It probably helped that he and Fuyuhiko frequently studied together.

He did feel a bit bad, though, that Fuyuhiko had to miss seeing the way Peko's eyes lit up while holding a purring Puffskein in her hands.

The first dose of Polyjuice Potion was due to wear off halfway through the lunch hour, so once their morning classes were finished, he and Fuyuhiko briefly met up outside the Great Hall to confirm their plan for the rest of the day.

"How are things going?" Hajime asked when he saw, well, himself arrive.

"Fine," Fuyuhiko answered. "Peko and Natsumi figured me out right away—"

"Wait— _right away_?!"

"—but I don't think anyone else has noticed. Everything good on your end?"

Hajime blinked up at him for a moment before managing to formulate a response. "Uh, yeah. Yeah, I don't think anyone has noticed. Definitely not immediately, at least."

Fuyuhiko rolled his (Hajime's?) eyes. "Yeah, yeah, laugh it up," he groaned, prompting Hajime to chuckle just as instructed.

With the decision made to take their second dose of the potion, the boys entered the Great Hall and briefly bumped fists before going their separate ways to their designated House tables.

This was what Hajime had been looking forward to—true, unrestrained socialization with Hufflepuffs. He couldn't be anymore friendly or talkative than the real Fuyuhiko would be, of course, but at least he'd be treated like he belonged.

Hajime found an empty seat across from Chiaki and Makoto and sat down. "Hey," he said, careful to add sufficient huffiness to pass as Fuyuhiko. "How were morning classes?"

Chiaki turned away from her conversation with Mikan on her other side to smile at him sleepily. "They were fine. How about you?"

Hajime shrugged. "Same as always, I guess."

"Oh, I see." Chiaki tilted her head thoughtfully. "But Hajime, why are you in Fuyuhiko's body?"

Makoto nearly choked on a piece of cornbread. "What?!" he coughed, looking at Hajime in alarm. "That's Hajime? I didn't even notice..."

"How could you not?" Chiaki chided, puffing her cheeks in indignation. "Isn't he your cousin?"

"Well yeah, but..."

Hajime sighed. So much for going undetected.

 **8**

The day had been long, tiring, and, Hajime had to admit, too nerve-wracking to really make the House swap worth it. While it was fun to give something different a try, the anxiety over blowing his cover to even more people had worn him down over the afternoon. It was a little surprising to admit it, but Hajime was actually looking forward to turning back and returning to Slytherin.

And judging by Fuyuhiko's (Hajime's?) haggard expression when they met up in front of the Barnabas the Barmy tapestry that afternoon, he felt the same way.

Hajime chuckled knowingly. "Ready to change back?"

"Fuck yes," Fuyuhiko muttered. "Why did we do this on a day you had Arithmancy? I couldn't follow shit."

Grinning weakly, Hajime turned his attention to the empty wall in front of them. "Well, the potion's about to wear off. Let's get this room open." He pivoted on his heel and paced in front of the wall once, twice, three times.

Both boys stared expectantly at the empty wall. Nothing happened.

"...Y-you must have been thinking of it wrong," Fuyuhiko said, clearly grasping for anything besides the worst possible scenario. "Let me do it."

Determined, Fuyuhiko strode past the wall three times, to no avail.

They stood in silence for a moment.

"Someone else is in there," Hajime said finally, vocalizing the unfortunate but obvious conclusion.

"Yeah."

"I didn't bring my change of clothes with me. Did you?"

"Nope. It's in the Room."

Hajime felt a slight chill at his ankles as his trousers seemed to become shorter with every passing moment.

"I think we need to find the nearest restroom."

* * *

 **Notes:** Some miscellaneous points I think I should mention.

-I wasn't sure whether to make the Imposter a Metamorphmagus or a Polyjuice expert—the former totally fit with his canon talent, but I reeeeaally wanted the latter for the sake of this story... so I just... went with both? haha.

-The class 77 kids are in the same year as Teddy Lupin, thus the mention of a second Metamorphmagus. I feel awkward about DR characters interacting with actual HP characters though (I felt iffy enough about mentioning Slughorn by name), so Teddy himself will probably never appear in this AU, haha.

-I read another AU once where Hinata and Naegi were cousins and I liked the idea so... poof. They're cousins now. *jazz hands* Yay.


End file.
